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Functional programmingIn computer science, functional programmingis a programming paradigm that treatscomputation as the evaluation ofmathematical functions and avoids state andmutable data. It emphasizes the application offunctions, in contrast to the imperative programmingstyle, which emphasizes changes in state.HTTP://EN.WIKIPEDIA.ORG/WIKI/FUNCTIONAL_PROGRAMMING

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Scala is a modern multi-paradigmprogramming language designed to expresscommon programming patterns in a concise, elegant,and type-safe way. It smoothly integrates featuresof object-oriented and functional languages.HTTP://WWW.SCALA-LANG.ORG/NODE/104Scala is also a functional languagein the sense that every function is avalue.